Crozo 
Inner Circle
Registration Date: 23.02.2012
Posts: 235
Herkunft: Française
 |
|
| Famille des Harpetidae (Hawle & Corda, 1847) |
     |
Classification : Harpetida - Harpetina - Harpetoidea
Représentant type de cette famille : Harpes (Goldfuss, 1839)
Diagnose générale de cette famille :
Céphalon : d’une façon générale il est semi-circulaire, ovale.
Avec un prolongement du bouclier céphalique par de fortes pointes.
Bouclier céphalique granuleux ou perforé par des centaines de fosses,
Ou présence chez certains genre des caecums génaux.
Glabelle rappelant le nez d’un humain, relativement fusiform, possédant
De 1 à 3 Paires de sillons glabellaire pas toujours très marqués.
Sur le côté de la glabelle présence constante de 2 lobes latéraux
Ovoïdes ou triangulaires, lobes dits pré-occipitaux. Anneau occipital convexe.
Surface visuelle très petites, on parle ici de tubercules avec 2 lentilles
Semi-circulaire adjacent aux lobes glabellaires postérieurs et relié par
Une crête oculaire bien marquée.
Thorax : composé de 12 (eoharpes) à 29 (harpes) segments thoraciques.
Plèvres droites et se finissant légèrement inclinées.
Pygidium : petit court, triangulaire, avec peu de segments.
Répartition : de l’Ordovicien inférieur au Dévonien supérieur
Ma collection de Harpetidae :
Crozo has attached these images (downsized versions):
  
|
|
08.03.2012 08:54 |
|
|
|
Crozo
Inner Circle
Registration Date: 23.02.2012
Posts: 235
Herkunft: Française
Thread Starter 
|
|
|
|
08.03.2012 08:54 |
|
|
| |
Jens
Moderator
Registration Date: 18.03.2007
Posts: 2,167
Herkunft: HGW, momentan Jura, Schweiz
|
|
Hi Crozo,
again some interesting trilobites. The Harpetida are really a high interesting order and we discussed about this here in the forum at length.
The first specimen seems to me a bit different to the real Harpes, with a more round shape, a feature we know from Bohemoharpes. I agree that the specimen comes from the Pragian and Petite Oufaten is probably only another word for the locality l'Atchana.
And for the last one, determinated as Harpes perradiatus from the Pragian, that can't be right. It's okay to label that one as a Harpes, but the species H. perradiatus looks complete different, with coarse pits at the brim. I own the original publication in which the type is figured.
By the way, all what normally called Harpes perradiatus from the Maider basin belongs not to the species described by Richter & Richter. Your specimen is probably from the Lower Eifelian of the Issoumour, where especially in the region of Bou Dib similar specimens were collected for the market by local trilobite hunters.
For the moment I can't give a proper determination, probably the 2 known species from Eifelian of the northern Maider are undescribed and new.
regards,
Jens
|
|
|
08.03.2012 14:19 |
|
|
|
Crozo
Inner Circle
Registration Date: 23.02.2012
Posts: 235
Herkunft: Française
Thread Starter
|
|
I think that there is a big main part work to make still on this family of "harpetidae", especially from Morocco. We can observe many differences on these specimens Moroccan. He is true that mine (see above) in him(it) thorax fossilized in right angle (usual posture to this kind). Thank you and to sson.
|
|
|
14.03.2012 08:46 |
|
|
|
Jens
Moderator
Registration Date: 18.03.2007
Posts: 2,167
Herkunft: HGW, momentan Jura, Schweiz
|
|
Hi Crozo,
| quote: |
Original von Crozo
I think that there is a big main part work to make still on this family of "harpetidae", especially from Morocco. We can observe many differences on these specimens Moroccan. |
Yes, as for many other devonial trilobites of Morocco, there are much left, which are not described or bad known. Especially the Harpidae got not much attention.
| quote: |
| Original von CrozoHe is true that mine (see above) in him(it) thorax fossilized in right angle (usual posture to this kind). Thank you and to sson. |
Yes, I made similar observations, a good part of Eifelian Harpes-specimens of Morocco have the thorax oriented in the 90° downwards directed position. Many collectors prefer the outstretched ones, but such specimens are rare.
At the moment I work on my own Harpes, also with that mentioned thorax-position. I'm not sure if this is the normal position, because outstretched specimens look normal too;-) And also in other places of the world, a outstretched thorax seems to be find in many specimens.
But I agree, there is somewhat special with this position. Because I observed a minute undulation of the thorax. Its difficult to explain. The thorax goes straight down, but there are minure ups and downs in the orientation of the frequent segment. May be its visible when I have finished the preparation.
For the moment I give only the link to the not finished specimen.
Präparation von "Was ist das" - 3 - gelöst: Harpes sp.
regards,
Jens
PS: Keep going your work in presenting us your huge collection, its unbelievable how many different specimens you have collect.
|
|
|
15.03.2012 16:49 |
|
|
Fred
Inner Circle
Registration Date: 24.10.2008
Posts: 238
|
|
I randomly picked one of these topics to express my admiration at your efforts to bring us a systematic overview of these trilobite families.
Nice, congrats, we like it and more of the same, please! 
|
|
|
15.03.2012 16:26 |
|
|
Privacy policy
|
We do need more Harpetids! 